- Caloric content and glycemic index of the diet in chronic kidney disease
- Protein and kidneys
- The importance of fat in chronic kidney disease
- How many carbohydrates to eat?
- Minerals - phosphorus and calcium
- Minerals - potassium
- Should sodium intake be reduced in case of kidney disease?
Kidney disease often forces you to change your eating habits. Some food products aggravate the symptoms associated with a given disease, and some nutrients accelerate the development of the disease. That is why it is so important that the diet in chronic kidney disease is carried out by a dietitian and that the patient strictly follows the recommendations of a specialist.
Caloric content and glycemic index of the diet in chronic kidney disease
A properly balanced diet in terms of calories is of great importance in the case of kidney disease, because the excess caloric content and obesity related to it may contribute to the progression of the disease, as well as lead to the development of comorbidities such as: hypertension, atherosclerosis.
Unfortunately, in patients with chronic kidney disease, there is a tendency for adipose tissue to dominate over muscle tissue, so from the very beginning they are more predisposed to metabolic disorders and gaining excess body weight.
For this reason, the amount of energy a patient should consume is 30-35 kcal / kg, with 65% of energy coming from carbohydrates, fat should be 30%, and protein the remaining 5%.
A dietitian planning a diet for a person with kidney disease should not forget to include regular physical activity in it ( although it is sometimes difficult to implement, because patients usually show greater fatigue and weakness). This allows the patient to obtain more muscle tissue, and thus improve the insulin metabolism.
In turn, the diet, in addition to balancing the correct calorific value and appropriate composition of the proportion of macronutrients, should be based on products with a low glycemic index. Such a diet allows you to reduce the risk of insulin resistance (very often it accompanies patients with kidney diseases) and accelerates the reduction of body fat.
Protein and kidneys
In kidney diseases, it is recommended to introduce a low-protein diet, because it allows you to lower the concentration of urea in the blood. Urea is the end product of protein metabolism that is formed during a process known as the urea cycle.
First, during the conversion of proteins, ammonia, which is toxic to the body, is created, and then it is neutralized toless harmful urea. And although it does not poison like ammonia, its accumulation is not beneficial for the body.
Increased urea levels lead to oliguria or anuria. In the final stage of chronic kidney disease, with too much accumulated urea, uremia may even develop, which can be recognized by:
- severe weakening,
- loss of appetite,
- reduced resistance to infections,
- or more fatigue.
In kidney disease, the supply of protein is significantly reduced, reducing its amount from, for example, 0.8 g per kg of body weight to 0.6 g or less. In patients with chronic kidney disease, whose condition is balanced and they do not have comorbidities such as diabetes, it is recommended to consume 0.6 g of protein per kilogram of body weight per day.
In advanced stages of chronic kidney disease, on the other hand, protein is administered in an amount below 0.4 g per kg / d with simultaneous inclusion of ketoanalogues (these are compounds that resemble amino acids in structure, but are devoid of nitrogen, which is conducive to increasing the concentration of urea in the blood).
The significant benefits of a low-protein diet include not only lowering the serum urea concentration, but also:
- phosphate concentration reduction,
- correcting the lipid profile,
- reduction of metabolic acidosis (disorders between acids and bases),
- reduction of hyperkalemia (excess potassium),
- improvement of insulin sensitivity,
- delay in the development of the disease.
The importance of fat in chronic kidney disease
Due to the limited supply of protein, fats should not be reduced in the diet. However, as a minimum, you should use saturated fatty acids, which may constitute at most 7% of the allowable 30% of energy derived from lipids.
This is mainly due to the fact that people with chronic kidney disease very often also have concomitant metabolic diseases, e.g. diabetes, which disturb the lipid metabolism. The saturated fats that should be used to a small extent include, among others butter, cream, cheese or fatty meat.
In turn, the remaining 23% of energy derived from fats should be allocated to monounsaturated and polyunsaturated fats. The advantage here should be fats rich in anti-inflammatory omega-3 fatty acids found in fatty fish such as salmon, mackerel, herring or oils such as linseed or rapeseed.
In addition, omega-6 fatty acids, which can be found in evening primrose oil, borage oil, andor sunflower oil. They have a positive effect on the body, but because they compete with omega-3 acids in the body and can limit their availability, it is worth consuming them in moderation.
In addition, the diet of people with kidney diseases should also include monounsaturated fatty acids such as: olive oil or sesame oil.
How many carbohydrates to eat?
Due to the fact that the amount of protein in the diet is significantly reduced and the amount of fat cannot be consumed as much again, you should take into account the amount of carbohydrates in the diet in the amount of 65% of the daily energy.
However, they should be valuable carbohydrates, such as: groats, wholemeal bread, wholemeal pasta or brown rice.
Minerals - phosphorus and calcium
The kidneys are the organ that regulates the levels of calcium and phosphorus. When its functioning is deteriorated, the economy of these elements is disturbed. Therefore, in chronic kidney disease, it is recommended to limit phosphorus intake to 800-1000 mg / day.
Products rich in phosphorus include: milk, cheese, eggs, buckwheat, sunflower seeds.
You should avoid consuming them in large amounts ( although they are limited in a low-protein diet for people with kidney problems), which at the same time, unfortunately, can lead to calcium deficiency (often the same products that contain phosphorus also contain calcium ).
In order to prevent calcium deficiencies, it is sometimes necessary to supplement it, but this is decided by the doctor.
Minerals - potassium
The initial stages of renal failure may lead to increased potassium loss. You should then take care to deliver products that contain a large amount of it, e.g. tomatoes, bananas, sweet potatoes.
As kidney disease develops and its functions weaken, excessive accumulation of potassium in the body and an increase in its concentration in the blood occurs, which results, among other things, in hyperkalemia. You should then limit the level of potassium consumed to 2000-2500 mg / day.
In order to reduce its amount, the diet should, for example, soak vegetables longer and cook dishes longer. In addition, reduce the consumption of: sweet potatoes, tomatoes, avocados, potatoes, apricots, soybeans, etc.
It is best to do it under the supervision of a dietitian and a doctor to avoid a significant depletion of this element in the daily menu.
Should sodium intake be reduced in case of kidney disease?
Chronic kidney disease leads to a decreased ability to excrete sodium. So when it comes to the situation that the patient develops swelling, increased thirst or arterial hypertension,then its consumption should be limited to 5 mg per day.
Sodium is found not only in the s alt we use to s alt our food. It is hidden in various food products that we would not suspect, e.g. corn flakes, rolls, meats.
In addition, we can find it in large amounts in: canned food, smoked meats, pickles, crisps, yellow cheese or stock cubes.